Telephone-receiver.



PAI'ENTED NOV. 19, 1907.

H. E. BOOTH. TELEPHONE RECEIVER.

APPLICATION FILED SEPT. 8,1902.

JZZAZ I-IIRAM E. BOOTH, or SALT LAKE cI'rY, UTAH.

TELEPHONE-RECEIVER.

Specification of Letters Patent.

, Patented Nov. 19, 1907.

Application filed September a 1902. as a. 122.517.

To all whom "it may concern:

Be'it known that l, llinau E. Room, a citizen of the United States of America, and

resident of Salt liake (-ity, balt Lake county,

Utah, have invented a certain new and useful 1m rovemcnt in 'lclephone-ltcccivers, oi whic r the following is a specification.

My invention contemplates a telephone receiver having an auxiliary diaphragm adapted toniodify and clarify the tones in such manner as to relieve them of all harshness and render them very clear and distinct. fll urthermore, my invention contemplates a telephone receiver having a supplemental or auxiliary diaphragurol a more or less porous and non-vibratory elntracter, and

- thus adapted to, not only, as stated, render the'tones more distinct and agreeable to the ear, but, inaddition, ti prcchuleall possibility of shock or injury to the ear or ear drum, such 'a'sinight result from the sudden changes of potential on the telephone line,

porous and non-vibratory diaphragm.

as in making and breaking connections, and particularlyas is the case in some telephone systems when batteries are cut out of circuit. More specifically, my invention contemplates an auxiliary diaphragm having a multitude of very fine openings.

In the accompanying drawings, Figure l is a longitudinal section oia telephone rereivor embodying the principles of my invention. Fig.2 is a sectional view o'l another form of Fig. 3 is a perspective or my improved dia phragm, showing the same composed oi three layers. Fig. 4' shows a diaphragm composed of but one layer.

As thus illustrated, my improved telephone receiver may comprise a casing A of any suitable known or a liprovml form. The.

. olectro-magnets B may a so be of anysuilablc form or character. The usual metallic and vibratory diaphragm G can be arranged in front of the magnets in .t'hcusual manner. In accordance with my invention, however, a supplemental diaphragm I) is'prezl'erably arrangeddirectly in front of "the vibratory diaphragm C, it being observed that the two diaphragnis are preferably separated to an extent su'llicient to provide a resonance chamber In other words, the two diaphragms are referably se arated. by an intervening bocy or air. 0th diaphragms can be. held upon the end of the casing by the cap F, which can be screwed upon the casing A. A separating rings can be employed for maintaining the proper distance between the two diaphragms. to clamp the two. dia hragms, and also the ring, securely upon 't 1c end oi the casing. The said sup )lcmental or auxiliary diaphragm is preferably of sullicient thickness to be more or less non-vibratory in charac ter, and also preferably porous in character. l or example, 'it may be composed of one or more layers 01' cloth, cotton wadding or some similar fibrous material arranged in sheets or layers. Again, it maybe composed ol front and backmetal latesd-withintervening layers o'l" cloth or fa )ric of any character, these twofront and back plates or disks, being provided with a multitude of fine openin s, such as might characterize a couple of dis (s oi "iine wire gauze oriincly erforated disks of hard rubber, metal, wooc, glass or the like. Thus it will be seen that this auxiliary diaphragm, which, as stated, is preferably of a non-vibratory and porous character, may be composed of various materials, such as metal wood, cloth, glass or any similar materiahi being preferable, however, that the materials employed are of a character to provide a diaphragm which, as stated, is more or less nonvibratory in character. At any rate, I find that very goorhand perhaps the best, results are obtained by employing a diaphragm composed of one or more layers of cloth or cotton wadding, or by using, as stated, a conple of perforated disks of glass, wood, hard rubber, metal, isinglass or the like, with glazed cotton wedding, cloth or other fibrous material between them. It is obvious, however, that various materials maybe employed for this purpose, and for this reason 1 do not limit in sell to any particular material or materias for constructing the diaphragm. Now with a telephone receiver thus constructed with a vibralory or sound producing diaphragm, and also with a porous and non\*ibratr )ry diaihragm, l lind that the sounds are relieved of all harshness and are also clarified and made very distinct and agreeable. to the ear. This will be oi particular-value in long distance telephone systems, as I lind that by emplo'yinga receiver of this character on a long distance line, I experience no dil'liculty whatever in receiving and understand ing conversationtransmitted from the other end of the line. I also lind that with a'receiver of this character the op- In this way, thecap serves an on the line, such as might result abm cut-" ting out batteries and testin the line, or

ringing :the bell while the receiver is held to.- the ear, without causing shock or injury to" the ear-drum, and practically without producing-any irritation whatever to the ear.

pla'ined, is preferably fof a oro'us and nonvibratory character. In t is Way, the receiver, as explained, involves a vibratory and a non-vibratory diaphragm with an intervening airspace. I- would suggest that in order to secure the best results'that'minerals or'metals, woods or hard rubber or'other influence of the electro-magnets.

phragm shown in Fig. 2.

materials that are non-magnetic be employed for the auxiliarydia hragni; It is" possible that any and all meta s and materials may be employed with more or less satisfac- 'tory results, but it is obvious that better rethis character, the diaphragm-Will not be at.-

rtracted when the electro-magnets are ener- I find. that verygood results can be obtained in producing clearness of the sound or i voice by using a vibratory 'diaphragmas the electro-magne t, and consequently disagree able, and shocks and vibrations are apt to be 5 receiver. But'whenan air space is left beauxiliary diaphragm, but-in such case I find that the auxiliary diaphragm is vibrated by the diaphragm immediately in froritfof the conveyed to the ear of the person using the .tween the two diaphragms, and wh'enthe auxiliary diaphragm is. non vibratory and characterized-by a multitudeof fine open ings, the receiver is rendered far superior'to those having but a single diaphragm. --This;

is so when the auxiliary diaphragm is made ofa thin sheet or sheets of isinglass or glass'or other like materials. But where a vibratory auxiliary diaphragm is used the injury to the, ear orear drum is a t'to be the same as yviththe ordinary singlet iaphragm; By the term non-vibratory I do not necessarily mean an absolutely rigid diaphragm ,"but, merely a. diaphragm less vibratory than the dia hragm "vibrated .b'y'the electre rnagnet, an imme 'diately in front of the latter. The-auxiliary "sound to reach'the ear, after being softened I guished from a diaphragm whichis merely.

.posed fibrous material. v

able casing, an electro-magnet, a vibiatory' With materials of diaphragm is preferably constructed so that it will have but little, if any, vibration, but if porous as herein described, will permit the and clarified and rendered. extremely agree ablerto the ear. And by porous diaphra in, I mean a diaphragm which is compose of material having minute pores as distinperforated. by a non-vibratory diaphragm, I mean a diaphragm-which is practically non-vibratory, or which is non-reso nant, so to speak. P J

I claim as my invention-- v 1. In-atelephone receiver,-the combination of a vibratory diaphragm,'-me ans for causing saiddiaphragm to vibrate for the purpose of producing sound waves, and a'jporous and non-vibratory diaphragm arranged to" re-=1 ceive the sound-waves propagated the vvibratorydiaphragm, with an air space'be-uf tween, said last mentioned diaphra m' con-- sisting offront and back disks with inter 2. A telephone receiver comprising a suitdia hragm arranged in front of said magnet, an an auxiliary dia hragm arranged in front of said vibratory iaphragm, with an air space between, said auxiliary diaphragm consisting of front and back sheets of pefio j rated material with interposed-fibrous mate-1 rial. 5'

3. A telephone receiver comprising a suit- 1 .abl e casing, an electromagnet, a vibratory dia hragm arranged in front ofsaid magnet, an a porous and non-vibratory diaphragm arranged, in frontof said vibratory dia-.

non-magnetic material having a mu titude of .fine openings'and with interposedfibrous and u porous material.

a. A telephone receiver comprismg a suitable casing, an electro-magnet, a vibratory A an auxiliary dia hragm arranged in front diagihragm arranged in front of said magnet,

iaphragm, with an air of said vibratory '[s'pace between, said auxiliarydiaphragm ,bejing less vibratory'than the saiddiaphragm n 1i0 front of saidfmagnet and consisting of a su1table number of perforatedsheets of hard material with interposed fibrous material. I Signed by me at Salt Lake City, Salt Lake 'co'unt'y, Utah, this 25 day of August, 1902.

v HI RAM i i BOOTH; Witnessesi a i EDDY O. L nn: I

MORRIS L. RITCHIE. 

